From: the.beez.speaks@gmail.com   
      
   On 30-06-2025 11:44, Paul Rubin wrote:   
   > zbigniew2011@gmail.com (LIT) writes:   
   >> "Pick and Roll are the generic operators which treat the data stack as   
   >> an array. If you find you need to use them, you are probably doing it   
   >> wrong. Look for ways to refactor your code to be simpler instead."   
   >   
   > What is the origin of that quote?  PICK treats the stack like an array,   
   > but ROLL treats it more as a circular shift register.   
   >   
   > Most CPUs these days have a register file, which is essentially an array   
   > with only immediate-like addressing mode.  Presumably that design   
   > evolved because programmers found it useful.   
   >   
   > PICK afaict is mostly used with literal offsets as well.  Having a   
   > variable offset is suspicious.   
   >   
   > : 3DUP ( a b c -- a b c a b c )  3 PICK 3 PICK 3 PICK ;   
   >   
   > Seems clearer than some mess of ROT and return stack temporaries.   
      
   If I so desperately wanted it I'd make a primitive out of it:   
      
   CODE (3DUP)      DSIZE (3); DFREE (3);   
                     a = DS(3); DPUSH (a);   
                     a = DS(3); DPUSH (a);   
                     a = DS(3); DPUSH (a); NEXT;   
      
   However - I use it RARELY. So, it's not worth the trouble to hardcode it.   
      
   $ pp4th -x stackopt.4th abc abcabc   
   - Trying a 1 word solution..   
   No solutions.   
   - Trying a 2 word solution..   
   No solutions.   
   - Trying a 3 word solution..   
   No solutions.   
   - Trying a 4 word solution..   
   No solutions.   
   - Trying a 5 word solution..   
   No solutions.   
   - Trying a 6 word solution..   
   No solutions.   
   - Trying a 7 word solution..   
    >r over over r@ rot rot r>   
   $   
      
   That'll do.   
      
   Hans Bezemer   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)